# Re: \[PATCH 2/3\] HID: valve-index: Reboot headset on system power transitions

- From: Mario Limonciello \<mario.limonciello@amd.com\>
- Date: 2026-09-11 06:01:52 
- List: linux-input
- Page: https://ratatoskr.run/linux-input/2026/09/17550451
- Thread: https://ratatoskr.run/linux-input/2026/09/17547710/t.md

```text


On 9/11/26 00:54, Greg Kroah-Hartman wrote:
> On Thu, Sep 10, 2026 at 12:02:53PM -0500, Mario Limonciello wrote:
>> The Valve Index HMD stops serving its EDID after the host disables the
>> DisplayPort PHY.  The headset remains powered by its breakout box across
>> suspend and shutdown, so the bad state survives and the next connector
>> detection reports "No EDID read".  The HMD then appears as a synthesized
>> 640x480 display until it is power-cycled.
>>
>> The 64-byte HID output report 0x16 with command 0x01 reboots the headset
>> and restores its EDID service.  Add a device-specific driver which sends
>> this report for system sleep transitions and orderly shutdown while leaving
>> runtime autosuspend alone.
>>
>> Resume a runtime-suspended interface for a shutdown request and restrict
>> the command to the composite interface which declares report 0x16.
>>
>> Closes: https://gitlab.freedesktop.org/drm/amd/-/work_items/4333
>> Link: https://github.com/ValveSoftware/SteamVR-for-Linux/issues/939
>> Assisted-by: LLM
>> Co-developed-by: Curtis Vogt <redacted>
>> Signed-off-by: Curtis Vogt <redacted>
>> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
>> ---
>>   .../ABI/testing/sysfs-driver-hid-valve-index  |  12 ++
>>   drivers/hid/Kconfig                           |  11 ++
>>   drivers/hid/Makefile                          |   1 +
>>   drivers/hid/hid-ids.h                         |   1 +
>>   drivers/hid/hid-valve-index.c                 | 142 ++++++++++++++++++
>>   5 files changed, 167 insertions(+)
>>   create mode 100644 Documentation/ABI/testing/sysfs-driver-hid-valve-index
>>   create mode 100644 drivers/hid/hid-valve-index.c
>>
>> diff --git a/Documentation/ABI/testing/sysfs-driver-hid-valve-index b/Documentation/ABI/testing/sysfs-driver-hid-valve-index
>> new file mode 100644
>> index 0000000000000..47d8c26b1eace
>> --- /dev/null
>> +++ b/Documentation/ABI/testing/sysfs-driver-hid-valve-index
>> @@ -0,0 +1,12 @@
>> +What:		/sys/bus/hid/devices/<bus>:<vid>:<pid>.<n>/reboot
>> +Date:		October 2026
>> +Contact:	linux-input@vger.kernel.org
>> +Description:
>> +		Writing a boolean true value reboots the Valve Index headset to
>> +		recover its EDID service. Writing a boolean false value has no
>> +		effect. This file is write-only.
>
> Shouldn't this just be a debugfs file?  Making it a sysfs file seems
> "risky" as it's not a normal operation.

Yeah I guess that makes sense.

>
>> +		The Valve Index is a composite HID device. The reboot command is
>> +		only supported by the interface that provides the headset's 64-byte
>> +		output report. Writing true to this file on another interface fails
>> +		with -ENODEV.
>
> Why would it be present on "another interface'?  That feels wrong.
>
> thanks,
>
> greg k-h

```